The present disclosure relates to a printer that is configured to perform printing on a printing medium by using heat and to a non-transitory computer-readable medium.
A printer is known that performs printing on a printing medium using a thermal line head that includes a plurality of heating elements. The heating elements for a single line of an image that will be formed are arrayed in a main scanning direction on the thermal line head. The printer may operate the thermal line head by applying an electric current to the heating elements, causing the heating elements to generate heat.
A method has been proposed for limiting the electric power that is consumed when the thermal line head is operated. For example, a method is disclosed for detecting a number of ON dots in printing data for one line and controlling the number of the heating elements that are heated based on the number of the detected ON dots. An outline of the method will be explained. The plurality of the heating elements that are provided in the thermal line head are divided into a plurality of blocks. In a case where the number of the detected ON dots is low, the printer heats the heating elements in all of the blocks at the same time. In this case, the printing of the entire line will be performed all at once, so the time that will be required in order to print the line may be short. Therefore, the printer can feed the printing medium at high speed, so can perform high-speed printing.
On the other hand, in a case where the number of the detected ON dots is large, the printer heats the heating elements at a different time for each block. In this case, the printing of the line will be performed by being divided into a plurality of rounds, so the time that will be required in order to print the line will become longer than in the case described above, where the printing of the entire line is performed all at once. Therefore, the printer cannot feed the printing medium at high speed. Accordingly, the printing medium is fed at low speed. As described above, the printer performs printing on the printing medium while switching the feed speed of the printing medium in accordance with the number of the detected ON dots.